In the related art, a mobile terminal (like a mobile phone) is equipped with an electroacoustic component, and a sound from the electroacoustic component is transmitted through a through hole in a housing for the terminal. Since a sound output hole is in communication with the outside, if the sound output hole is too large, impurities (such as dust) from the outside can easily enter the housing from the sound output hole, thereby causing damages to parts in the housing; if the sound output hole is too small, the sound from the electroacoustic component is difficult to be transmitted through the sound output hole, hence lowering a sound volume of the electroacoustic component or even resulting in silence, thereby degrading user experience.